The present invention relates to processes for the preparation of 5-[[2(R)-[1(R)-[3,5-bis(trifluoromethyl)phenyl]ethoxy]-3(S)-(4-fluorophenyl)-4-morpholinyl]methyl]-1,2-dihydro-3H-1,2,4-triazol-3-one, aprepitant,
which is a useful therapeutic agent, specifically as a substance P (neurokinin-1) receptor antagonist. This compound is disclosed as having therapeutic utility in U.S. Pat. No. 5,719,147.
U.S. Pat. Nos. 5,637,699, 6,096,742, 6,229,010 and 6,297,376 relate to processes of manufacture and the discovery of polymorphic forms of this compound. In contrast to previously known processes, the present invention provides a more practical and economical method for preparing the compound in relatively high yield and purity. As such, there is a need for a process for the preparation of the compound that is cost-effective and utilizes readily available reagents.